FI103214B - Provides for measuring the body diameter - Google Patents

Description

103214

APPARATUS FOR MEASURING THE Diameter of a Piece

The invention relates to a device for measuring the diameter of a body comprising a body and a probe 5 connected thereto with an actuator, a measuring roll fitted on the measuring head, a first sensor for measuring the rotation of the measuring roll and a device for processing values of said sensors.

SU patent application No. 1460597 discloses a device for measuring the diameter by means of an auxiliary roll so that the number of revolutions of the auxiliary roll, whose diameter is precisely known, is determined per revolution. This gives the roll circuit and is further computed in diameter. However, many computational components make this system complicated.

SU Patent Publication No. 675302 discloses a device for measuring the diameter and shape of a body. In said measuring device-20, two interconnected rollers are applied which are pivotally attached to the actuator. The rolls are considerably smaller than the piece to be measured. At the time of measurement, the piece rotates. Then, as the rollers rotate, the sensors connected to them send a sinusoidal signal to a separate calculator. Signal-25 determines the diameter of the part and the shape deviation with respect to the cylinder. The measurement arrangement based on sine waves is inaccurate.

The known auxiliary roller solutions are particularly susceptible to possible slip of the 30 auxiliary rollers, which immediately causes a large measurement error. On the other hand, contamination of rolling surfaces, especially the auxiliary roller, results in a measurement error both directly and secondary in the form of increasing slip.

The object of the invention is to provide an accurate and versatile device for measuring the diameter of a round piece of a roll or the like. The measuring device according to the invention is more reliable and accurate than before and is independent of environmental conditions. Characteristic features of the present invention will be apparent from the appended claims 2,103,214. The hard metal has a high coefficient of friction against steel, which primarily prevents slipping.

The invention will now be described in detail with reference to the accompanying drawings, in which:

Fig. 1 shows a measuring device according to the invention mounted on a machine tool;

Figure 3 is a front and partially sectional view of the measuring device of Figure 1.

Figure 1 shows a measuring device 2 according to the invention 15 mounted on a machine tool 1. The measuring device 2 is moved along the longitudinal axis of the roller 3 by means of horizontal guides 5. The measuring device 2 is placed in the normal blade holder of the machining machine 20 and positioned with the machine's own positioning system. To accurately determine the rotational movement of the roll 3, the machine tool 1 has an optical sensor 7 that detects a mark 8 at the end of the roll 3. The measuring device 2 is provided with flexible electrical and compressed air connections (not shown) for operating it, which allow the diameter to be measured over the entire length of the roll 3.

; The measuring device 2 includes a probe 12 connected to its body 10 by means of guides 11. The actual measurement of the diameter is based on the rotation of the measuring roll 13 and the roll 3 and measuring it.

For this purpose, the probe 12 has a measuring roll 13 and a pulse sensor 14 connected thereto. The measured values of the rotation movement of the roll 35 3 and the measuring roll 13 and the known characteristics of the measuring roll 13 measured by said sensors 7 and 14. For the determination, the values of the sensors 7 and 14 are passed to a separate device, preferably a computer (not shown in 3 103214), whereby accurate, pulse-transmitting sensors can be used. Pulse encoder with 10000 pulses per revolution has been used for testing the measuring device 2.

Figure 2 shows the components of the measuring device 2 in more detail. By means of said guides 11, the probe 12 can move in the longitudinal direction of the body 10. The movement is performed by a pneumatic cylinder 6 to which compressed air is conveyed through 16. A measuring roller 13 is mounted on the probe head 12. This measuring roller 13 comprises a 10-piece structure with a carbide ring 18 on top of the carbon fiber inner disc 17, since the friction coefficient between carbide and steel is good, the structure can eliminate slip between Further, the carbon-15 fiber-resin ratio of said composite ring 13 is adjusted so that the coefficient of expansion of the inner disk 17 is the same as that of ring 18. In this case, the coefficient of thermal expansion of both is preferably 6.5 x 10 6 l / K. The adjustment of the coefficient is also influenced by the orientation of the carbon fibers.

20

In addition, a cap 20 is provided on the housing 19 at the probe 12 against the measuring roll 13 to keep the ring 18 clean. The elastic blade 21 of the two-piece scraper 20 is always in contact with the surface of the ring 18. The blade 21 is disposed in the direction of rotation of the measuring roller 13. The blade 21 is further depressed by a rigid support 22 which prevents the blade 21 from coming off the ring 18. The scraper 20 can also be mounted on both sides of the measuring roll 13, allowing both directions of rotation of the measuring roll 13. The cleaning effect of the blade 21 is enhanced by the air flow supplied to the measuring roll 30, which blows the impurities away from the roll 3 and the measuring roll 13. Said air flow to the probe is conducted through a hose 23.

Airflow has another purpose besides cleaning. 35 By arranging an adjustable air heater (not shown) in the pneumatic line, the temperature of the measuring roller 13 can be kept constant. In addition, the axial temperature variation of the object to be measured can be taken into account. For a long roll with a diameter of 4 103214, a change of 2 ° C affects the diameter by 0.05 mm. There are sensors (not shown) for measuring temperature at both probe 12 and the pneumatic line. IR sensors are preferably used to measure roll temperature.

5

Fig. 3 shows the measuring device 2 in partial section and the cover 19 of the measuring roll 13 removed. It also appears from the figure that the ring 18 of the measuring roller 13 is narrower than the inner disk 17. The break-through box on the right side of the measuring roll 13 is a pneumatic-driven turbine 24. With the turbine 24, the speed of the measuring roller 13 can be adjusted to match the speed of the pre-rotating roller 3. Auxiliary rotation reduces the possibility of slipping and also eliminates bearing frictions 15 at the probe 12.

The pulse sensor 14, the turbine 24 and the measuring roll 13, which measure the rotation of the measuring roller 13, are arranged on the same shaft 25, which is represented by a dashed line. In this case, no play is created and the rotating masses 20 are small, which makes the measuring device 2 sensitive. Sensitive in this context means the rapid adaptation of the measuring device 2 to the conditions and the smooth rotation of the measuring roller 13. The composite structure of the measuring roller 13 also reinforces this property because the mass of the measuring roller 13 is centered on the ring 18. Figure 3 further shows the electrical connection 26 of the pulse sensor 14 to the computer.

On both sides of the body 10 are linear guides 11 for positioning the probe 12. Preferably, ball-rotation guides 30 are used. The conductors 11 in question have a very low resting friction, so that the probe 12 is sensitive to movement. In addition, the conductors li are obtained) I Ψ free of play. The measuring device 2 further comprises a pneumatic single-acting spring-return cylinder 6 housed within its body 10, in order to stabilize the contact pressure exerted by the measuring roller 13 on the measuring body 35 of the cylinder 6 with an operating pressure regulator (not shown). Said regulator, or pressure equalizer, also compensates for the movement caused by the eccentricity of the body to be measured at constant pressure.

5, 103214

The measuring device 2 according to the invention, due to its construction, has a short installation length but good adaptability. Eccentric rotating bodies can also be measured. The carbide ring 18 of the measuring roller 13 can be machined to exact dimensions and will not wear during use. In addition, the measuring device 2 is software calibrable.

The measuring device 2 is experimentally independent of the temperature of the measured object in the range of 15-45 ° C and of ambient temperature-10 variations. In addition, the measuring device 2 operates under production conditions independent of dust, dirt and heat flows. Measurement during machining is also possible. One measuring device 2 covers a wide outside and inside measuring range. Furthermore, the lightweight measuring device 2 is easy to install, for example, on the machine tool 1 and the measuring device 2 can be used to make multiple measurements at various locations. The measuring device 2 can be fitted to the various brackets simply by replacing a suitable bracket with a bolt connection to the body 10. The measurement is automatic so one person can perform it. On the other hand, the measurement result of the calibrated measuring device 2 does not depend on the person performing the measurement.

The measuring device 2 according to the invention can also be applied by means of various sensors. The number of sensors may also vary.

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Claims (10)

Device for measuring the diameter of a piece, the device (2) comprising the chassis (10) and to this coupled measuring probe (12), for which positioning there is an operating device (6) between them, a measuring roller (6) is provided for the measuring probe ( 13), a first sensor (14) for determining the rotational motion of the measuring roller (13) and a second sensor (7) for determining the rotational motion of the measuring object (3), and means for processing the said sensors (7, 14). ), characterized in that the measuring roller (13) consists of a two-part structure, in which there is a ring (18) of thermoset metal on the inner pulley (17). r Device according to claim 1, characterized in that the inner pulley (17) is of composite carbon fiber, in which the structure of the carbon fiber and the resin as well as the fiber direction is arranged so that the coefficient of thermal expansion of the inner pulley (17) is the same as for rings (18). «8 103214 Device according to claim 1 or 2, characterized in that a rotating means (24) is provided for the measuring probe (12) to adjust the speed of the measuring roller (13) to correspond in advance to the speed of the already rotating piece (3). 5 Device according to any of claims 1 to 3, characterized in that a cleaner (20) has been arranged on the measuring probe (20) against the measuring roller (13) to keep the ring (18) clean. Device according to any of claims 1-4, characterized in that in the device (2) there are conduits (23) and control means for directing the temperature-controlled air flow to the vicinity of the measuring roller (13). Device according to claim 5, characterized in that, for the control of the air flow, the control devices are arranged to cooperate with the temperature sensor which is adjacent to the measuring roller (13). Device according to any one of claims 1-6, characterized in that the actuating member (6) includes an operating pressure regulator for stabilizing the pressure applied by the measuring roller (13) to the piece (3) to be measured. Device according to any one of claims 1-7, characterized in that the measuring probe (12) is coupled to the chassis (10) with linear control (11), which is presumably of ball rotation principle. Device according to any of claims 3-8, characterized in that said first sensor (14), the rotating means (24) and the measuring roller (13) are arranged on the same shaft (25). 10. Device according to any one of claims 3-9, characterized in that the actuator (6) and the rotary member (24) are compressed air driven. *